Isotropic / anisotropic soft magnetic material: spline saturation curve


This model defines a nonlinear B(H) dependence for an isotropic starting from the experimental B, H values.

The definition of the B(H) curve with this model is a little longer than with the analytic models, but the experimental curve is modeled more accurately.

Mathematical model

The model is constructed in the following manner:

  • entry of experimental B, H values
  • interpolation by a spline function

The shape of the B(H) curve is given in the figure below.

Advice (regarding software)

The spline saturation curve must have only one knee.

If your device operates with higher values of the magnetic field, where magnetic saturation may be reached, you must not describe the knee of the B(H) curve near the origin, and conversely if you work at a low magnetic field.

Anisotropic material

For an anisotropic material, this linear model consists of a group of three straight lines.

This model is taken into account with the following conditions:

  • 2D applications (2D plane domain): Magneto Static / Transient magnetic
  • regions: magnetic non conducting, solid conductor